wouter van ooijen wrote:
>>> Note that this code still requires that all jump table
>> entries are in
>>> the same 256-instructions page. For a jumptable that crosses a page
>>> boundary (hence for all >256 entries tables) you will have to
>>> calculate the value to load into PCLATH.
>>
>> Unless I'm really missing something here, I don't understand
>> why you say
>> that.  His technique takes into consideration that a page is being
>> crossed and appropriately increments PCLATH by 1 when that is
>> happening.
>
> Sorry, you are right. I did not look well enough.

I don't know why Microchip doesn't tout doing it this way.  It's only a 
few instructions more and makes the table floatable.    Here is how I 
did it for a character table on a 16F88:

get_msg_char
                movfw       msg_ptr             ; get desired offset 
from beginning of string
                btfss       PORTA, DIRECTION    ; Check direction
                 sublw      message_size - 1    ; When going CCW, we 
must fetch letters in reverse order
                addlw       3
                addwf       PCL, W              ; Add offset and current 
PCL
                skpnc                           ; Check for page 
crossing
                 incf       PCLATH, F           ;  and compensate for it
                movwf       PCL                 ; Fetch the value
message         dt "MESSAGE TEXT GOES HERE"
message_size    equ     $ - message

I intentionally forced the text to cross a page boundary and all was 
well.  The 3 being added is for the skpnc, incf and movwf instructions.


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